Fluxon

In physics, a fluxon is a quantum of electromagnetic flux. The term may have any of several related meanings.

In the context of superconductivity, in type II superconductors fluxons (also known as an Abrikosov vortices) can form when the applied field lies between ${\displaystyle B_{c_{1}}}$ and ${\displaystyle B_{c_{2}}}$. The fluxon is a small whisker of normal phase surrounded by superconducting phase, and Supercurrents circulate around the normal core. The magnetic field through such a whisker and its neighborhood, which has size of the order of London penetration depth ${\displaystyle \lambda _{L}}$ (~100 nm), is quantized because of the phase properties of the magnetic vector potential in quantum electrodynamics, see magnetic flux quantum for details.

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